Air seeding apparatus for crop farming is typically mounted on a trailer towed behind a tractor or other farming machinery. The air seeder includes at least one seed and/or seed/soil supplement product frame-mounted hopper for storing seed and/or supplement product in granular form to be planted or spread over farmland. Supplement product includes, but is not limited to, fertilizer, inoculants, herbicide, etc. The seed and supplement product will generally be referred to herein as product. It is generally advantageous to tow an air seeder in combination with tilling equipment in order to place the seed and supplement product beneath the surface of the soil.
Air seeders typically employ a metering system for dispensing product from the hopper and a pneumatic distribution system for delivering the metered product to the soil. Air seeders that can separately meter seed and supplement product are available having distribution systems that can apply both seed and supplement product such as fertilizer simultaneously to a field.
A known metering system for an air seeder includes a volumetric meter that is geared to the wheels of the air seeder trailer to dispense a fixed volume of product per unit of linear distance traveled by the air seeder. A volumetric meter typically includes either augers or a fluted cylinder mounted at the bottom of the hopper, product from the hopper filling the interstitial spaces thereon. Rotating the volumetric meter against a screed measures out the granular product in units of interstitial volumes. Thereafter, the product so dispensed is allowed to enter the pneumatic distribution system.
The pneumatic distribution system generally utilizes air under pressure to provide at least one air stream that flows through the pneumatic distribution system and carries the product to be deposited in the soil, typically by seed boots. Product dispensed by the metering system is first introduced into the air stream at a primary distribution manifold. Fluidized product is carried under air pressure by primary distribution lines to a group of secondary distribution manifolds (“headers”), which in turn distribute product through secondary distribution lines to individual seed boots mounted behind ground openers on the tilling implement. The metering of the product dispensed may evenly deliver the product along a furrow made by a corresponding opener of the tilling equipment.
The uniform spreading of product across a field is important to successful farming operations. Typically, each secondary distribution manifold services a number of seed boots, and as such each secondary distribution manifold has product intake requirements proportional to the number of ground openers and seed boots serviced. Since the total number of ground openers of the tilling equipment is often not evenly divisible by the number of secondary distribution manifolds of the air seeder, at least one secondary distribution manifold may be servicing a different number of seed boots than other secondary distribution manifolds of the same tilling equipment.
Therefore, in order to evenly distribute product across the width of the tilling equipment, product seen by a secondary distribution header that, for example, is servicing 9 seed boots, should be less than ( 9/10) the amount of product seen by a secondary distribution header servicing 10 seed boots. The meter upstream in the pneumatic distribution system from the secondary distribution header servicing fewer seed boots should therefore supply a correspondingly lesser volume of product compared to other meters. However, all meters employed in dispensing a product from a particular hopper typically share, and are driven by, a common shaft.
A known method for reducing the product metering rate involves using a meter roller comprised of individual sections of varying widths, with spacers to their sides. Another method employs same size meter roller sections with separators therebetween and blanks between separators to block out portions of the interstitial volumes of meter roller sections.
However, these prior art meter rollers are cumbersome to use, as there are many individual parts that need to be assembled. Furthermore, the use of spacers, blanks and the like present a lot of nooks for product to get lodged in, particularly under high humidity conditions, which tends to clump the product in nooks. Product left in the metering system from the last use of the air seeder may contaminate the next product being dispensed. The undesirable adherence of product therefore renders the air seeder time inefficient for mixed-crop farming operations, which require fast turnaround.
Therefore, there is a need in the crop farming industry to provide a metering system that, in conjunction with a pneumatic distribution system and tilling equipment, provides substantially uniform product distribution across the tillage.
There is a need in the crop farming industry to provide a metering system which can accommodate varying product volume dispensing requirements with respect to individual meter roller sections driven by a common shaft wherein each meter roller section corresponds to a secondary distribution manifold.
There is a need in the crop farming industry to provide a metering system providing improved time efficiencies for mixed-crop farming operations.